Absorbent products, such as diapers and sanitary napkins, generally utilize three distinctive layers: a top, body-facing layer, normally a fluid permeable sheet for engaging with body fluids, a core, usually a fluid absorbent material such as wood pulp for retaining fluids, and a bottom layer, usually a fluid impervious barrier film. In these constructions, body fluids permeate through the body-facing layer into the absorbent core where they are absorbed and stored. Traditionally, the body-facing layer has been made from a soft, non-woven web which generally allows fluid to migrate into the absorbent core and separates the body from the discharge to keep the skin clean and dry. The main drawback to such non-woven facing materials is that some fluid is often retained in the capillary structure of the web, resulting in a wet surface disposed against the user. Recently, facing materials made from apertured film, such as polyethylene, have been used to overcome the wetness problem. In the absence of capillaries, very little fluid is retained on the film and a drier surface against the skin is obtained. Apertured films have the added advantage that, since they are more opaque than non-woven webs, they can better hide the stained absorbent core. However the plastic apertured films generally are less comfortable to wear than non-woven facing materials.
Some of the problems associated with comfort and performance of absorbent products have been addressed in such patents as: Fox, U.S. Pat. No. 2,551,663, issued May 8, 1951; Erdman et al., U.S. Pat. No. 4,676,784, issued Jun. 30, 1987; Nishino, U.S. Pat. No. 4,676,786, issued Jun. 30, 1987; Rosenbaum, U.S. Pat. No. 4,643,727, issued Feb. 17, 1987; Taylor, U.S. Pat. No. 3,889,679, issued Jun. 17, 1975; and Green, U.S. Pat. No. 810,130, issued Jan. 16, 1906.
Erdman et al., for example, describes absorbent products comprising resilient fibers and super absorbent materials. This reference teaches the use of a hydrophilic porous cover and a fibrous superstructure containing at least about 10% by weight superabsorbent. The fibrous superstructure comprises apertures or strips of a web in a configuration which provides channels for attracting fluid.
Nishino describes a paper diaper having a surface layer of fluff pulp with a "partition layer" having spaced openings therein, followed by a "crust layer" disposed under the partition layer to receive and diffuse fluids in an oriented manner.
Rosenbaum describes an absorbent pad having an intermediate "plastic bubble layer" covered on either side with a continuous layer of absorbent material. The bubble layer of this reference serves as a reservoir for fluid that is eventually syphoned around the edges of the bubble layer for storage.
Taylor discloses a disposable diaper comprising an absorbent body and a water impervious backing sheet. The absorbent body is provided with a plurality of fluid passages for distributing fluid to more remote portions of its structure.
Green describes an absorbent bandage which utilizes internal cells for the quick reception of fluid. These cells distribute the fluid to an absorbent fibrous mass for storage. The bandage can further comprise a fabric cover.
Fox describes a catamenial diaper having an elongated pad having a longitudinally extending chamber therein and a plurality of vertical openings for transmitting fluid from the top of the pad to the chamber. This catamenial diaper employs rubber materials and is designed to be reusable.
Although these references disclose useful techniques for comfort and absorption, there has been a long-felt need for a composite cover which combines the comfort of a fibrous web with the opacity and dryness of an apertured film, while overcoming their deficiencies.